blob: 4f9f69e22c1bd3c2f63c17f245d95f67e3565ca3 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Linux ARCnet driver - device-independent routines
3 *
4 * Written 1997 by David Woodhouse.
5 * Written 1994-1999 by Avery Pennarun.
6 * Written 1999-2000 by Martin Mares <mj@ucw.cz>.
7 * Derived from skeleton.c by Donald Becker.
8 *
9 * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
10 * for sponsoring the further development of this driver.
11 *
12 * **********************
13 *
14 * The original copyright was as follows:
15 *
16 * skeleton.c Written 1993 by Donald Becker.
17 * Copyright 1993 United States Government as represented by the
18 * Director, National Security Agency. This software may only be used
19 * and distributed according to the terms of the GNU General Public License as
20 * modified by SRC, incorporated herein by reference.
21 *
22 * **********************
23 *
24 * The change log is now in a file called ChangeLog in this directory.
25 *
26 * Sources:
27 * - Crynwr arcnet.com/arcether.com packet drivers.
28 * - arcnet.c v0.00 dated 1/1/94 and apparently by
29 * Donald Becker - it didn't work :)
30 * - skeleton.c v0.05 dated 11/16/93 by Donald Becker
31 * (from Linux Kernel 1.1.45)
32 * - RFC's 1201 and 1051 - re: TCP/IP over ARCnet
33 * - The official ARCnet COM9026 data sheets (!) thanks to
34 * Ken Cornetet <kcornete@nyx10.cs.du.edu>
35 * - The official ARCnet COM20020 data sheets.
36 * - Information on some more obscure ARCnet controller chips, thanks
37 * to the nice people at SMSC.
38 * - net/inet/eth.c (from kernel 1.1.50) for header-building info.
39 * - Alternate Linux ARCnet source by V.Shergin <vsher@sao.stavropol.su>
40 * - Textual information and more alternate source from Joachim Koenig
41 * <jojo@repas.de>
42 */
43
44#define VERSION "arcnet: v3.93 BETA 2000/04/29 - by Avery Pennarun et al.\n"
45
46#include <linux/module.h>
47#include <linux/config.h>
48#include <linux/types.h>
49#include <linux/delay.h>
50#include <linux/netdevice.h>
51#include <linux/if_arp.h>
52#include <net/arp.h>
53#include <linux/init.h>
54#include <linux/arcdevice.h>
55
56/* "do nothing" functions for protocol drivers */
57static void null_rx(struct net_device *dev, int bufnum,
58 struct archdr *pkthdr, int length);
59static int null_build_header(struct sk_buff *skb, struct net_device *dev,
60 unsigned short type, uint8_t daddr);
61static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
62 int length, int bufnum);
63
64
65/*
66 * one ArcProto per possible proto ID. None of the elements of
67 * arc_proto_map are allowed to be NULL; they will get set to
68 * arc_proto_default instead. It also must not be NULL; if you would like
69 * to set it to NULL, set it to &arc_proto_null instead.
70 */
71 struct ArcProto *arc_proto_map[256], *arc_proto_default,
72 *arc_bcast_proto, *arc_raw_proto;
73
74struct ArcProto arc_proto_null =
75{
76 .suffix = '?',
77 .mtu = XMTU,
78 .is_ip = 0,
79 .rx = null_rx,
80 .build_header = null_build_header,
81 .prepare_tx = null_prepare_tx,
82 .continue_tx = NULL,
83 .ack_tx = NULL
84};
85
86/* Exported function prototypes */
87int arcnet_debug = ARCNET_DEBUG;
88
89EXPORT_SYMBOL(arc_proto_map);
90EXPORT_SYMBOL(arc_proto_default);
91EXPORT_SYMBOL(arc_bcast_proto);
92EXPORT_SYMBOL(arc_raw_proto);
93EXPORT_SYMBOL(arc_proto_null);
94EXPORT_SYMBOL(arcnet_unregister_proto);
95EXPORT_SYMBOL(arcnet_debug);
96EXPORT_SYMBOL(alloc_arcdev);
97EXPORT_SYMBOL(arcnet_interrupt);
98
99/* Internal function prototypes */
100static int arcnet_open(struct net_device *dev);
101static int arcnet_close(struct net_device *dev);
102static int arcnet_send_packet(struct sk_buff *skb, struct net_device *dev);
103static void arcnet_timeout(struct net_device *dev);
104static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
105 unsigned short type, void *daddr, void *saddr,
106 unsigned len);
107static int arcnet_rebuild_header(struct sk_buff *skb);
108static struct net_device_stats *arcnet_get_stats(struct net_device *dev);
109static int go_tx(struct net_device *dev);
110
111static int debug = ARCNET_DEBUG;
112module_param(debug, int, 0);
113MODULE_LICENSE("GPL");
114
115static int __init arcnet_init(void)
116{
117 int count;
118
119 arcnet_debug = debug;
120
121 printk(VERSION);
122
123#ifdef ALPHA_WARNING
124 BUGLVL(D_EXTRA) {
125 printk("arcnet: ***\n"
126 "arcnet: * Read arcnet.txt for important release notes!\n"
127 "arcnet: *\n"
128 "arcnet: * This is an ALPHA version! (Last stable release: v3.02) E-mail\n"
129 "arcnet: * me if you have any questions, comments, or bug reports.\n"
130 "arcnet: ***\n");
131 }
132#endif
133
134 /* initialize the protocol map */
135 arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null;
136 for (count = 0; count < 256; count++)
137 arc_proto_map[count] = arc_proto_default;
138
139 BUGLVL(D_DURING)
140 printk("arcnet: struct sizes: %Zd %Zd %Zd %Zd %Zd\n",
141 sizeof(struct arc_hardware), sizeof(struct arc_rfc1201),
142 sizeof(struct arc_rfc1051), sizeof(struct arc_eth_encap),
143 sizeof(struct archdr));
144
145 return 0;
146}
147
148static void __exit arcnet_exit(void)
149{
150}
151
152module_init(arcnet_init);
153module_exit(arcnet_exit);
154
155/*
156 * Dump the contents of an sk_buff
157 */
158#if ARCNET_DEBUG_MAX & D_SKB
159void arcnet_dump_skb(struct net_device *dev,
160 struct sk_buff *skb, char *desc)
161{
162 int i;
163
164 printk(KERN_DEBUG "%6s: skb dump (%s) follows:", dev->name, desc);
165 for (i = 0; i < skb->len; i++) {
166 if (i % 16 == 0)
167 printk("\n" KERN_DEBUG "[%04X] ", i);
168 printk("%02X ", ((u_char *) skb->data)[i]);
169 }
170 printk("\n");
171}
172
173EXPORT_SYMBOL(arcnet_dump_skb);
174#endif
175
176
177/*
178 * Dump the contents of an ARCnet buffer
179 */
180#if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
181void arcnet_dump_packet(struct net_device *dev, int bufnum, char *desc,
182 int take_arcnet_lock)
183{
184 struct arcnet_local *lp = dev->priv;
185 int i, length;
186 unsigned long flags = 0;
187 static uint8_t buf[512];
188
189 /* hw.copy_from_card expects IRQ context so take the IRQ lock
190 to keep it single threaded */
191 if(take_arcnet_lock)
192 spin_lock_irqsave(&lp->lock, flags);
193
194 lp->hw.copy_from_card(dev, bufnum, 0, buf, 512);
195 if(take_arcnet_lock)
196 spin_unlock_irqrestore(&lp->lock, flags);
197
198 /* if the offset[0] byte is nonzero, this is a 256-byte packet */
199 length = (buf[2] ? 256 : 512);
200
201 printk(KERN_DEBUG "%6s: packet dump (%s) follows:", dev->name, desc);
202 for (i = 0; i < length; i++) {
203 if (i % 16 == 0)
204 printk("\n" KERN_DEBUG "[%04X] ", i);
205 printk("%02X ", buf[i]);
206 }
207 printk("\n");
208
209}
210
211EXPORT_SYMBOL(arcnet_dump_packet);
212#endif
213
214
215/*
216 * Unregister a protocol driver from the arc_proto_map. Protocol drivers
217 * are responsible for registering themselves, but the unregister routine
218 * is pretty generic so we'll do it here.
219 */
220void arcnet_unregister_proto(struct ArcProto *proto)
221{
222 int count;
223
224 if (arc_proto_default == proto)
225 arc_proto_default = &arc_proto_null;
226 if (arc_bcast_proto == proto)
227 arc_bcast_proto = arc_proto_default;
228 if (arc_raw_proto == proto)
229 arc_raw_proto = arc_proto_default;
230
231 for (count = 0; count < 256; count++) {
232 if (arc_proto_map[count] == proto)
233 arc_proto_map[count] = arc_proto_default;
234 }
235}
236
237
238/*
239 * Add a buffer to the queue. Only the interrupt handler is allowed to do
240 * this, unless interrupts are disabled.
241 *
242 * Note: we don't check for a full queue, since there aren't enough buffers
243 * to more than fill it.
244 */
245static void release_arcbuf(struct net_device *dev, int bufnum)
246{
247 struct arcnet_local *lp = dev->priv;
248 int i;
249
250 lp->buf_queue[lp->first_free_buf++] = bufnum;
251 lp->first_free_buf %= 5;
252
253 BUGLVL(D_DURING) {
254 BUGMSG(D_DURING, "release_arcbuf: freed #%d; buffer queue is now: ",
255 bufnum);
256 for (i = lp->next_buf; i != lp->first_free_buf; i = (i+1) % 5)
257 BUGMSG2(D_DURING, "#%d ", lp->buf_queue[i]);
258 BUGMSG2(D_DURING, "\n");
259 }
260}
261
262
263/*
264 * Get a buffer from the queue. If this returns -1, there are no buffers
265 * available.
266 */
267static int get_arcbuf(struct net_device *dev)
268{
269 struct arcnet_local *lp = dev->priv;
270 int buf = -1, i;
271
272 if (!atomic_dec_and_test(&lp->buf_lock)) {
273 /* already in this function */
274 BUGMSG(D_NORMAL, "get_arcbuf: overlap (%d)!\n",
275 lp->buf_lock.counter);
276 }
277 else { /* we can continue */
278 if (lp->next_buf >= 5)
279 lp->next_buf -= 5;
280
281 if (lp->next_buf == lp->first_free_buf)
282 BUGMSG(D_NORMAL, "get_arcbuf: BUG: no buffers are available??\n");
283 else {
284 buf = lp->buf_queue[lp->next_buf++];
285 lp->next_buf %= 5;
286 }
287 }
288
289
290 BUGLVL(D_DURING) {
291 BUGMSG(D_DURING, "get_arcbuf: got #%d; buffer queue is now: ", buf);
292 for (i = lp->next_buf; i != lp->first_free_buf; i = (i+1) % 5)
293 BUGMSG2(D_DURING, "#%d ", lp->buf_queue[i]);
294 BUGMSG2(D_DURING, "\n");
295 }
296
297 atomic_inc(&lp->buf_lock);
298 return buf;
299}
300
301
302static int choose_mtu(void)
303{
304 int count, mtu = 65535;
305
306 /* choose the smallest MTU of all available encaps */
307 for (count = 0; count < 256; count++) {
308 if (arc_proto_map[count] != &arc_proto_null
309 && arc_proto_map[count]->mtu < mtu) {
310 mtu = arc_proto_map[count]->mtu;
311 }
312 }
313
314 return mtu == 65535 ? XMTU : mtu;
315}
316
317
318/* Setup a struct device for ARCnet. */
319static void arcdev_setup(struct net_device *dev)
320{
321 dev->type = ARPHRD_ARCNET;
322 dev->hard_header_len = sizeof(struct archdr);
323 dev->mtu = choose_mtu();
324
325 dev->addr_len = ARCNET_ALEN;
326 dev->tx_queue_len = 100;
327 dev->broadcast[0] = 0x00; /* for us, broadcasts are address 0 */
328 dev->watchdog_timeo = TX_TIMEOUT;
329
330 /* New-style flags. */
331 dev->flags = IFF_BROADCAST;
332
333 /*
334 * Put in this stuff here, so we don't have to export the symbols to
335 * the chipset drivers.
336 */
337 dev->open = arcnet_open;
338 dev->stop = arcnet_close;
339 dev->hard_start_xmit = arcnet_send_packet;
340 dev->tx_timeout = arcnet_timeout;
341 dev->get_stats = arcnet_get_stats;
342 dev->hard_header = arcnet_header;
343 dev->rebuild_header = arcnet_rebuild_header;
344}
345
346struct net_device *alloc_arcdev(char *name)
347{
348 struct net_device *dev;
349
350 dev = alloc_netdev(sizeof(struct arcnet_local),
351 name && *name ? name : "arc%d", arcdev_setup);
352 if(dev) {
353 struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
354 spin_lock_init(&lp->lock);
355 }
356
357 return dev;
358}
359
360/*
361 * Open/initialize the board. This is called sometime after booting when
362 * the 'ifconfig' program is run.
363 *
364 * This routine should set everything up anew at each open, even registers
365 * that "should" only need to be set once at boot, so that there is
366 * non-reboot way to recover if something goes wrong.
367 */
368static int arcnet_open(struct net_device *dev)
369{
370 struct arcnet_local *lp = dev->priv;
371 int count, newmtu, error;
372
373 BUGMSG(D_INIT,"opened.");
374
375 if (!try_module_get(lp->hw.owner))
376 return -ENODEV;
377
378 BUGLVL(D_PROTO) {
379 int count;
380 BUGMSG(D_PROTO, "protocol map (default is '%c'): ",
381 arc_proto_default->suffix);
382 for (count = 0; count < 256; count++)
383 BUGMSG2(D_PROTO, "%c", arc_proto_map[count]->suffix);
384 BUGMSG2(D_PROTO, "\n");
385 }
386
387
388 BUGMSG(D_INIT, "arcnet_open: resetting card.\n");
389
390 /* try to put the card in a defined state - if it fails the first
391 * time, actually reset it.
392 */
393 error = -ENODEV;
394 if (ARCRESET(0) && ARCRESET(1))
395 goto out_module_put;
396
397 newmtu = choose_mtu();
398 if (newmtu < dev->mtu)
399 dev->mtu = newmtu;
400
401 BUGMSG(D_INIT, "arcnet_open: mtu: %d.\n", dev->mtu);
402
403 /* autodetect the encapsulation for each host. */
404 memset(lp->default_proto, 0, sizeof(lp->default_proto));
405
406 /* the broadcast address is special - use the 'bcast' protocol */
407 for (count = 0; count < 256; count++) {
408 if (arc_proto_map[count] == arc_bcast_proto) {
409 lp->default_proto[0] = count;
410 break;
411 }
412 }
413
414 /* initialize buffers */
415 atomic_set(&lp->buf_lock, 1);
416
417 lp->next_buf = lp->first_free_buf = 0;
418 release_arcbuf(dev, 0);
419 release_arcbuf(dev, 1);
420 release_arcbuf(dev, 2);
421 release_arcbuf(dev, 3);
422 lp->cur_tx = lp->next_tx = -1;
423 lp->cur_rx = -1;
424
425 lp->rfc1201.sequence = 1;
426
427 /* bring up the hardware driver */
428 if (lp->hw.open)
429 lp->hw.open(dev);
430
431 if (dev->dev_addr[0] == 0)
432 BUGMSG(D_NORMAL, "WARNING! Station address 00 is reserved "
433 "for broadcasts!\n");
434 else if (dev->dev_addr[0] == 255)
435 BUGMSG(D_NORMAL, "WARNING! Station address FF may confuse "
436 "DOS networking programs!\n");
437
438 BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
439 if (ASTATUS() & RESETflag) {
440 BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
441 ACOMMAND(CFLAGScmd | RESETclear);
442 }
443
444
445 BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
446 /* make sure we're ready to receive IRQ's. */
447 AINTMASK(0);
448 udelay(1); /* give it time to set the mask before
449 * we reset it again. (may not even be
450 * necessary)
451 */
452 BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
453 lp->intmask = NORXflag | RECONflag;
454 AINTMASK(lp->intmask);
455 BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
456
457 netif_start_queue(dev);
458
459 return 0;
460
461 out_module_put:
462 module_put(lp->hw.owner);
463 return error;
464}
465
466
467/* The inverse routine to arcnet_open - shuts down the card. */
468static int arcnet_close(struct net_device *dev)
469{
470 struct arcnet_local *lp = dev->priv;
471
472 netif_stop_queue(dev);
473
474 /* flush TX and disable RX */
475 AINTMASK(0);
476 ACOMMAND(NOTXcmd); /* stop transmit */
477 ACOMMAND(NORXcmd); /* disable receive */
478 mdelay(1);
479
480 /* shut down the card */
481 lp->hw.close(dev);
482 module_put(lp->hw.owner);
483 return 0;
484}
485
486
487static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
488 unsigned short type, void *daddr, void *saddr,
489 unsigned len)
490{
491 struct arcnet_local *lp = dev->priv;
492 uint8_t _daddr, proto_num;
493 struct ArcProto *proto;
494
495 BUGMSG(D_DURING,
496 "create header from %d to %d; protocol %d (%Xh); size %u.\n",
497 saddr ? *(uint8_t *) saddr : -1,
498 daddr ? *(uint8_t *) daddr : -1,
499 type, type, len);
500
501 if (skb->len!=0 && len != skb->len)
502 BUGMSG(D_NORMAL, "arcnet_header: Yikes! skb->len(%d) != len(%d)!\n",
503 skb->len, len);
504
505
506 /* Type is host order - ? */
507 if(type == ETH_P_ARCNET) {
508 proto = arc_raw_proto;
509 BUGMSG(D_DEBUG, "arc_raw_proto used. proto='%c'\n",proto->suffix);
510 _daddr = daddr ? *(uint8_t *) daddr : 0;
511 }
512 else if (!daddr) {
513 /*
514 * if the dest addr isn't provided, we can't choose an encapsulation!
515 * Store the packet type (eg. ETH_P_IP) for now, and we'll push on a
516 * real header when we do rebuild_header.
517 */
518 *(uint16_t *) skb_push(skb, 2) = type;
519 if (skb->nh.raw - skb->mac.raw != 2)
520 BUGMSG(D_NORMAL, "arcnet_header: Yikes! diff (%d) is not 2!\n",
521 (int)(skb->nh.raw - skb->mac.raw));
522 return -2; /* return error -- can't transmit yet! */
523 }
524 else {
525 /* otherwise, we can just add the header as usual. */
526 _daddr = *(uint8_t *) daddr;
527 proto_num = lp->default_proto[_daddr];
528 proto = arc_proto_map[proto_num];
529 BUGMSG(D_DURING, "building header for %02Xh using protocol '%c'\n",
530 proto_num, proto->suffix);
531 if (proto == &arc_proto_null && arc_bcast_proto != proto) {
532 BUGMSG(D_DURING, "actually, let's use '%c' instead.\n",
533 arc_bcast_proto->suffix);
534 proto = arc_bcast_proto;
535 }
536 }
537 return proto->build_header(skb, dev, type, _daddr);
538}
539
540
541/*
542 * Rebuild the ARCnet hard header. This is called after an ARP (or in the
543 * future other address resolution) has completed on this sk_buff. We now
544 * let ARP fill in the destination field.
545 */
546static int arcnet_rebuild_header(struct sk_buff *skb)
547{
548 struct net_device *dev = skb->dev;
549 struct arcnet_local *lp = dev->priv;
550 int status = 0; /* default is failure */
551 unsigned short type;
552 uint8_t daddr=0;
553 struct ArcProto *proto;
554
555 if (skb->nh.raw - skb->mac.raw != 2) {
556 BUGMSG(D_NORMAL,
557 "rebuild_header: shouldn't be here! (hdrsize=%d)\n",
558 (int)(skb->nh.raw - skb->mac.raw));
559 return 0;
560 }
561 type = *(uint16_t *) skb_pull(skb, 2);
562 BUGMSG(D_DURING, "rebuild header for protocol %Xh\n", type);
563
564 if (type == ETH_P_IP) {
565#ifdef CONFIG_INET
566 BUGMSG(D_DURING, "rebuild header for ethernet protocol %Xh\n", type);
567 status = arp_find(&daddr, skb) ? 1 : 0;
568 BUGMSG(D_DURING, " rebuilt: dest is %d; protocol %Xh\n",
569 daddr, type);
570#endif
571 } else {
572 BUGMSG(D_NORMAL,
573 "I don't understand ethernet protocol %Xh addresses!\n", type);
574 lp->stats.tx_errors++;
575 lp->stats.tx_aborted_errors++;
576 }
577
578 /* if we couldn't resolve the address... give up. */
579 if (!status)
580 return 0;
581
582 /* add the _real_ header this time! */
583 proto = arc_proto_map[lp->default_proto[daddr]];
584 proto->build_header(skb, dev, type, daddr);
585
586 return 1; /* success */
587}
588
589
590
591/* Called by the kernel in order to transmit a packet. */
592static int arcnet_send_packet(struct sk_buff *skb, struct net_device *dev)
593{
594 struct arcnet_local *lp = dev->priv;
595 struct archdr *pkt;
596 struct arc_rfc1201 *soft;
597 struct ArcProto *proto;
598 int txbuf;
599 unsigned long flags;
600 int freeskb = 0;
601
602 BUGMSG(D_DURING,
603 "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
604 ASTATUS(), lp->cur_tx, lp->next_tx, skb->len,skb->protocol);
605
606 pkt = (struct archdr *) skb->data;
607 soft = &pkt->soft.rfc1201;
608 proto = arc_proto_map[soft->proto];
609
610 BUGMSG(D_SKB_SIZE, "skb: transmitting %d bytes to %02X\n",
611 skb->len, pkt->hard.dest);
612 BUGLVL(D_SKB) arcnet_dump_skb(dev, skb, "tx");
613
614 /* fits in one packet? */
615 if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
616 BUGMSG(D_NORMAL, "fixme: packet too large: compensating badly!\n");
617 dev_kfree_skb(skb);
618 return 0; /* don't try again */
619 }
620
621 /* We're busy transmitting a packet... */
622 netif_stop_queue(dev);
623
624 spin_lock_irqsave(&lp->lock, flags);
625 AINTMASK(0);
626
627 txbuf = get_arcbuf(dev);
628 if (txbuf != -1) {
629 if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
630 !proto->ack_tx) {
631 /* done right away and we don't want to acknowledge
632 the package later - forget about it now */
633 lp->stats.tx_bytes += skb->len;
634 freeskb = 1;
635 } else {
636 /* do it the 'split' way */
637 lp->outgoing.proto = proto;
638 lp->outgoing.skb = skb;
639 lp->outgoing.pkt = pkt;
640
641 if (proto->continue_tx &&
642 proto->continue_tx(dev, txbuf)) {
643 BUGMSG(D_NORMAL,
644 "bug! continue_tx finished the first time! "
645 "(proto='%c')\n", proto->suffix);
646 }
647 }
648
649 lp->next_tx = txbuf;
650 } else {
651 freeskb = 1;
652 }
653
654 BUGMSG(D_DEBUG, "%s: %d: %s, status: %x\n",__FILE__,__LINE__,__FUNCTION__,ASTATUS());
655 /* make sure we didn't ignore a TX IRQ while we were in here */
656 AINTMASK(0);
657
658 BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
659 lp->intmask |= TXFREEflag|EXCNAKflag;
660 AINTMASK(lp->intmask);
661 BUGMSG(D_DEBUG, "%s: %d: %s, status: %x\n",__FILE__,__LINE__,__FUNCTION__,ASTATUS());
662
663 spin_unlock_irqrestore(&lp->lock, flags);
664 if (freeskb) {
665 dev_kfree_skb(skb);
666 }
667 return 0; /* no need to try again */
668}
669
670
671/*
672 * Actually start transmitting a packet that was loaded into a buffer
673 * by prepare_tx. This should _only_ be called by the interrupt handler.
674 */
675static int go_tx(struct net_device *dev)
676{
677 struct arcnet_local *lp = dev->priv;
678
679 BUGMSG(D_DURING, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
680 ASTATUS(), lp->intmask, lp->next_tx, lp->cur_tx);
681
682 if (lp->cur_tx != -1 || lp->next_tx == -1)
683 return 0;
684
685 BUGLVL(D_TX) arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
686
687 lp->cur_tx = lp->next_tx;
688 lp->next_tx = -1;
689
690 /* start sending */
691 ACOMMAND(TXcmd | (lp->cur_tx << 3));
692
693 dev->trans_start = jiffies;
694 lp->stats.tx_packets++;
695 lp->lasttrans_dest = lp->lastload_dest;
696 lp->lastload_dest = 0;
697 lp->excnak_pending = 0;
698 lp->intmask |= TXFREEflag|EXCNAKflag;
699
700 return 1;
701}
702
703
704/* Called by the kernel when transmit times out */
705static void arcnet_timeout(struct net_device *dev)
706{
707 unsigned long flags;
708 struct arcnet_local *lp = dev->priv;
709 int status = ASTATUS();
710 char *msg;
711
712 spin_lock_irqsave(&lp->lock, flags);
713 if (status & TXFREEflag) { /* transmit _DID_ finish */
714 msg = " - missed IRQ?";
715 } else {
716 msg = "";
717 lp->stats.tx_aborted_errors++;
718 lp->timed_out = 1;
719 ACOMMAND(NOTXcmd | (lp->cur_tx << 3));
720 }
721 lp->stats.tx_errors++;
722
723 /* make sure we didn't miss a TX or a EXC NAK IRQ */
724 AINTMASK(0);
725 lp->intmask |= TXFREEflag|EXCNAKflag;
726 AINTMASK(lp->intmask);
727
728 spin_unlock_irqrestore(&lp->lock, flags);
729
730 if (jiffies - lp->last_timeout > 10*HZ) {
731 BUGMSG(D_EXTRA, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
732 msg, status, lp->intmask, lp->lasttrans_dest);
733 lp->last_timeout = jiffies;
734 }
735
736 if (lp->cur_tx == -1)
737 netif_wake_queue(dev);
738}
739
740
741/*
742 * The typical workload of the driver: Handle the network interface
743 * interrupts. Establish which device needs attention, and call the correct
744 * chipset interrupt handler.
745 */
746irqreturn_t arcnet_interrupt(int irq, void *dev_id, struct pt_regs *regs)
747{
748 struct net_device *dev = dev_id;
749 struct arcnet_local *lp;
750 int recbuf, status, diagstatus, didsomething, boguscount;
751 int retval = IRQ_NONE;
752
753 BUGMSG(D_DURING, "\n");
754
755 BUGMSG(D_DURING, "in arcnet_interrupt\n");
756
757 lp = dev->priv;
758 if (!lp)
759 BUG();
760
761 spin_lock(&lp->lock);
762
763 /*
764 * RESET flag was enabled - if device is not running, we must clear it right
765 * away (but nothing else).
766 */
767 if (!netif_running(dev)) {
768 if (ASTATUS() & RESETflag)
769 ACOMMAND(CFLAGScmd | RESETclear);
770 AINTMASK(0);
771 spin_unlock(&lp->lock);
772 return IRQ_HANDLED;
773 }
774
775 BUGMSG(D_DURING, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
776 ASTATUS(), lp->intmask);
777
778 boguscount = 5;
779 do {
780 status = ASTATUS();
781 diagstatus = (status >> 8) & 0xFF;
782
783 BUGMSG(D_DEBUG, "%s: %d: %s: status=%x\n",
784 __FILE__,__LINE__,__FUNCTION__,status);
785 didsomething = 0;
786
787 /*
788 * RESET flag was enabled - card is resetting and if RX is
789 * disabled, it's NOT because we just got a packet.
790 *
791 * The card is in an undefined state. Clear it out and start over.
792 */
793 if (status & RESETflag) {
794 BUGMSG(D_NORMAL, "spurious reset (status=%Xh)\n", status);
795 arcnet_close(dev);
796 arcnet_open(dev);
797
798 /* get out of the interrupt handler! */
799 break;
800 }
801 /*
802 * RX is inhibited - we must have received something. Prepare to
803 * receive into the next buffer.
804 *
805 * We don't actually copy the received packet from the card until
806 * after the transmit handler runs (and possibly launches the next
807 * tx); this should improve latency slightly if we get both types
808 * of interrupts at once.
809 */
810 recbuf = -1;
811 if (status & lp->intmask & NORXflag) {
812 recbuf = lp->cur_rx;
813 BUGMSG(D_DURING, "Buffer #%d: receive irq (status=%Xh)\n",
814 recbuf, status);
815
816 lp->cur_rx = get_arcbuf(dev);
817 if (lp->cur_rx != -1) {
818 BUGMSG(D_DURING, "enabling receive to buffer #%d\n",
819 lp->cur_rx);
820 ACOMMAND(RXcmd | (lp->cur_rx << 3) | RXbcasts);
821 }
822 didsomething++;
823 }
824
825 if((diagstatus & EXCNAKflag)) {
826 BUGMSG(D_DURING, "EXCNAK IRQ (diagstat=%Xh)\n",
827 diagstatus);
828
829 ACOMMAND(NOTXcmd); /* disable transmit */
830 lp->excnak_pending = 1;
831
832 ACOMMAND(EXCNAKclear);
833 lp->intmask &= ~(EXCNAKflag);
834 didsomething++;
835 }
836
837
838 /* a transmit finished, and we're interested in it. */
839 if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
840 lp->intmask &= ~(TXFREEflag|EXCNAKflag);
841
842 BUGMSG(D_DURING, "TX IRQ (stat=%Xh)\n", status);
843
844 if (lp->cur_tx != -1 && !lp->timed_out) {
845 if(!(status & TXACKflag)) {
846 if (lp->lasttrans_dest != 0) {
847 BUGMSG(D_EXTRA,
848 "transmit was not acknowledged! "
849 "(status=%Xh, dest=%02Xh)\n",
850 status, lp->lasttrans_dest);
851 lp->stats.tx_errors++;
852 lp->stats.tx_carrier_errors++;
853 } else {
854 BUGMSG(D_DURING,
855 "broadcast was not acknowledged; that's normal "
856 "(status=%Xh, dest=%02Xh)\n",
857 status, lp->lasttrans_dest);
858 }
859 }
860
861 if (lp->outgoing.proto &&
862 lp->outgoing.proto->ack_tx) {
863 int ackstatus;
864 if(status & TXACKflag)
865 ackstatus=2;
866 else if(lp->excnak_pending)
867 ackstatus=1;
868 else
869 ackstatus=0;
870
871 lp->outgoing.proto
872 ->ack_tx(dev, ackstatus);
873 }
874 }
875 if (lp->cur_tx != -1)
876 release_arcbuf(dev, lp->cur_tx);
877
878 lp->cur_tx = -1;
879 lp->timed_out = 0;
880 didsomething++;
881
882 /* send another packet if there is one */
883 go_tx(dev);
884
885 /* continue a split packet, if any */
886 if (lp->outgoing.proto && lp->outgoing.proto->continue_tx) {
887 int txbuf = get_arcbuf(dev);
888 if (txbuf != -1) {
889 if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
890 /* that was the last segment */
891 lp->stats.tx_bytes += lp->outgoing.skb->len;
892 if(!lp->outgoing.proto->ack_tx)
893 {
894 dev_kfree_skb_irq(lp->outgoing.skb);
895 lp->outgoing.proto = NULL;
896 }
897 }
898 lp->next_tx = txbuf;
899 }
900 }
901 /* inform upper layers of idleness, if necessary */
902 if (lp->cur_tx == -1)
903 netif_wake_queue(dev);
904 }
905 /* now process the received packet, if any */
906 if (recbuf != -1) {
907 BUGLVL(D_RX) arcnet_dump_packet(dev, recbuf, "rx irq", 0);
908
909 arcnet_rx(dev, recbuf);
910 release_arcbuf(dev, recbuf);
911
912 didsomething++;
913 }
914 if (status & lp->intmask & RECONflag) {
915 ACOMMAND(CFLAGScmd | CONFIGclear);
916 lp->stats.tx_carrier_errors++;
917
918 BUGMSG(D_RECON, "Network reconfiguration detected (status=%Xh)\n",
919 status);
920
921 /* is the RECON info empty or old? */
922 if (!lp->first_recon || !lp->last_recon ||
923 jiffies - lp->last_recon > HZ * 10) {
924 if (lp->network_down)
925 BUGMSG(D_NORMAL, "reconfiguration detected: cabling restored?\n");
926 lp->first_recon = lp->last_recon = jiffies;
927 lp->num_recons = lp->network_down = 0;
928
929 BUGMSG(D_DURING, "recon: clearing counters.\n");
930 } else { /* add to current RECON counter */
931 lp->last_recon = jiffies;
932 lp->num_recons++;
933
934 BUGMSG(D_DURING, "recon: counter=%d, time=%lds, net=%d\n",
935 lp->num_recons,
936 (lp->last_recon - lp->first_recon) / HZ,
937 lp->network_down);
938
939 /* if network is marked up;
940 * and first_recon and last_recon are 60+ apart;
941 * and the average no. of recons counted is
942 * > RECON_THRESHOLD/min;
943 * then print a warning message.
944 */
945 if (!lp->network_down
946 && (lp->last_recon - lp->first_recon) <= HZ * 60
947 && lp->num_recons >= RECON_THRESHOLD) {
948 lp->network_down = 1;
949 BUGMSG(D_NORMAL, "many reconfigurations detected: cabling problem?\n");
950 } else if (!lp->network_down
951 && lp->last_recon - lp->first_recon > HZ * 60) {
952 /* reset counters if we've gone for over a minute. */
953 lp->first_recon = lp->last_recon;
954 lp->num_recons = 1;
955 }
956 }
957 } else if (lp->network_down && jiffies - lp->last_recon > HZ * 10) {
958 if (lp->network_down)
959 BUGMSG(D_NORMAL, "cabling restored?\n");
960 lp->first_recon = lp->last_recon = 0;
961 lp->num_recons = lp->network_down = 0;
962
963 BUGMSG(D_DURING, "not recon: clearing counters anyway.\n");
964 }
965
966 if(didsomething) {
967 retval |= IRQ_HANDLED;
968 }
969 }
970 while (--boguscount && didsomething);
971
972 BUGMSG(D_DURING, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
973 ASTATUS(), boguscount);
974 BUGMSG(D_DURING, "\n");
975
976
977 AINTMASK(0);
978 udelay(1);
979 AINTMASK(lp->intmask);
980
981 spin_unlock(&lp->lock);
982 return retval;
983}
984
985
986/*
987 * This is a generic packet receiver that calls arcnet??_rx depending on the
988 * protocol ID found.
989 */
990void arcnet_rx(struct net_device *dev, int bufnum)
991{
992 struct arcnet_local *lp = dev->priv;
993 struct archdr pkt;
994 struct arc_rfc1201 *soft;
995 int length, ofs;
996
997 soft = &pkt.soft.rfc1201;
998
999 lp->hw.copy_from_card(dev, bufnum, 0, &pkt, sizeof(ARC_HDR_SIZE));
1000 if (pkt.hard.offset[0]) {
1001 ofs = pkt.hard.offset[0];
1002 length = 256 - ofs;
1003 } else {
1004 ofs = pkt.hard.offset[1];
1005 length = 512 - ofs;
1006 }
1007
1008 /* get the full header, if possible */
1009 if (sizeof(pkt.soft) <= length)
1010 lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(pkt.soft));
1011 else {
1012 memset(&pkt.soft, 0, sizeof(pkt.soft));
1013 lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1014 }
1015
1016 BUGMSG(D_DURING, "Buffer #%d: received packet from %02Xh to %02Xh "
1017 "(%d+4 bytes)\n",
1018 bufnum, pkt.hard.source, pkt.hard.dest, length);
1019
1020 lp->stats.rx_packets++;
1021 lp->stats.rx_bytes += length + ARC_HDR_SIZE;
1022
1023 /* call the right receiver for the protocol */
1024 if (arc_proto_map[soft->proto]->is_ip) {
1025 BUGLVL(D_PROTO) {
1026 struct ArcProto
1027 *oldp = arc_proto_map[lp->default_proto[pkt.hard.source]],
1028 *newp = arc_proto_map[soft->proto];
1029
1030 if (oldp != newp) {
1031 BUGMSG(D_PROTO,
1032 "got protocol %02Xh; encap for host %02Xh is now '%c'"
1033 " (was '%c')\n", soft->proto, pkt.hard.source,
1034 newp->suffix, oldp->suffix);
1035 }
1036 }
1037
1038 /* broadcasts will always be done with the last-used encap. */
1039 lp->default_proto[0] = soft->proto;
1040
1041 /* in striking contrast, the following isn't a hack. */
1042 lp->default_proto[pkt.hard.source] = soft->proto;
1043 }
1044 /* call the protocol-specific receiver. */
1045 arc_proto_map[soft->proto]->rx(dev, bufnum, &pkt, length);
1046}
1047
1048
1049
1050/*
1051 * Get the current statistics. This may be called with the card open or
1052 * closed.
1053 */
1054static struct net_device_stats *arcnet_get_stats(struct net_device *dev)
1055{
1056 struct arcnet_local *lp = dev->priv;
1057 return &lp->stats;
1058}
1059
1060
1061static void null_rx(struct net_device *dev, int bufnum,
1062 struct archdr *pkthdr, int length)
1063{
1064 BUGMSG(D_PROTO,
1065 "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1066 pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1067}
1068
1069
1070static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1071 unsigned short type, uint8_t daddr)
1072{
1073 struct arcnet_local *lp = dev->priv;
1074
1075 BUGMSG(D_PROTO,
1076 "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1077 lp->default_proto[daddr]);
1078
1079 /* always fails */
1080 return 0;
1081}
1082
1083
1084/* the "do nothing" prepare_tx function warns that there's nothing to do. */
1085static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1086 int length, int bufnum)
1087{
1088 struct arcnet_local *lp = dev->priv;
1089 struct arc_hardware newpkt;
1090
1091 BUGMSG(D_PROTO, "tx: no encap for this host; load a protocol driver.\n");
1092
1093 /* send a packet to myself -- will never get received, of course */
1094 newpkt.source = newpkt.dest = dev->dev_addr[0];
1095
1096 /* only one byte of actual data (and it's random) */
1097 newpkt.offset[0] = 0xFF;
1098
1099 lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1100
1101 return 1; /* done */
1102}